xref: /linux/include/media/cec-notifier.h (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * cec-notifier.h - notify CEC drivers of physical address changes
3  *
4  * Copyright 2016 Russell King <rmk+kernel@arm.linux.org.uk>
5  * Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
6  *
7  * This program is free software; you may redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; version 2 of the License.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
12  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
13  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
14  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
15  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
16  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
17  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
18  * SOFTWARE.
19  */
20 
21 #ifndef LINUX_CEC_NOTIFIER_H
22 #define LINUX_CEC_NOTIFIER_H
23 
24 #include <linux/types.h>
25 #include <media/cec.h>
26 
27 struct device;
28 struct edid;
29 struct cec_adapter;
30 struct cec_notifier;
31 
32 #ifdef CONFIG_MEDIA_CEC_NOTIFIER
33 
34 /**
35  * cec_notifier_get - find or create a new cec_notifier for the given device.
36  * @dev: device that sends the events.
37  *
38  * If a notifier for device @dev already exists, then increase the refcount
39  * and return that notifier.
40  *
41  * If it doesn't exist, then allocate a new notifier struct and return a
42  * pointer to that new struct.
43  *
44  * Return NULL if the memory could not be allocated.
45  */
46 struct cec_notifier *cec_notifier_get(struct device *dev);
47 
48 /**
49  * cec_notifier_put - decrease refcount and delete when the refcount reaches 0.
50  * @n: notifier
51  */
52 void cec_notifier_put(struct cec_notifier *n);
53 
54 /**
55  * cec_notifier_set_phys_addr - set a new physical address.
56  * @n: the CEC notifier
57  * @pa: the CEC physical address
58  *
59  * Set a new CEC physical address.
60  */
61 void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa);
62 
63 /**
64  * cec_notifier_set_phys_addr_from_edid - set parse the PA from the EDID.
65  * @n: the CEC notifier
66  * @edid: the struct edid pointer
67  *
68  * Parses the EDID to obtain the new CEC physical address and set it.
69  */
70 void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
71 					  const struct edid *edid);
72 
73 /**
74  * cec_notifier_register - register a callback with the notifier
75  * @n: the CEC notifier
76  * @adap: the CEC adapter, passed as argument to the callback function
77  * @callback: the callback function
78  */
79 void cec_notifier_register(struct cec_notifier *n,
80 			   struct cec_adapter *adap,
81 			   void (*callback)(struct cec_adapter *adap, u16 pa));
82 
83 /**
84  * cec_notifier_unregister - unregister the callback from the notifier.
85  * @n: the CEC notifier
86  */
87 void cec_notifier_unregister(struct cec_notifier *n);
88 
89 #else
90 static inline struct cec_notifier *cec_notifier_get(struct device *dev)
91 {
92 	/* A non-NULL pointer is expected on success */
93 	return (struct cec_notifier *)0xdeadfeed;
94 }
95 
96 static inline void cec_notifier_put(struct cec_notifier *n)
97 {
98 }
99 
100 static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
101 {
102 }
103 
104 static inline void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
105 							const struct edid *edid)
106 {
107 }
108 
109 #endif
110 
111 #endif
112